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Normal map tangent basis issues.


GIS3000
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Hi everyone,

I'm noticing some issues when it comes to importing  normal maps baked in Xnormal. Notice that there are rendering artifacts?

XnormalBaked.thumb.png.e336a117743d4adffc4b1a1e859da54d.png

This artifacts do not appear in Substance painter nor do they appear in Unity 5.6. They render perfectly. 

Painter.thumb.png.a8635aab21bee8d653688b603dfe71ab.png

In the preferences, I've checked to ensure that the Tangent Space Standard is set to MikkTSpace.  The normal map baked in 3D coat looks ok, thou.

internalBaked.thumb.png.0751b0c8585c4685f8643ba05f284888.png

Am I missing something? I've ensured that the obj model is triangulated and is smoothed before exporting.

Thanks for your time.

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1 hour ago, houGenie said:

I assume that the normal calculation is not the same across the different programs. Have you tried to change the normal calculation in the preferences?

Thanks for the reply.:)

Yes, all I know is that Xnormal and Painter both use MikkTspace. Not too sure about 3D coat. I find it strange that there are so many methods of configuring normal map tangent basis in 3D coat. You can set the normal calculation method and the tangent space separately, which kinda confuses me..... 

I've checked to ensure that the Tangent Space Standard is set to MikkTSpace

All options in the normal calculation method in the preferences have all been tried. None of them work. 

BTW, any way of importing a projection baking cage? And I can't seem to find the quality setting for the normal map baking.

 

I've attached my 2 models here. Hope that someone can help.

shape_Low.obj

Shape_High.FBX

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Why do you not use 3d coat for baking ? I have tried it with the unreal preset in the preferences and the normal maps look fine. See picture.

Yes there are a lot of settings to be aware of, but this is better than to not be able to change this settings, because depending of your target you need this options!

MikkTSpace should be the correct one. And the normal calculation setting is important too, because depending on how XNormal calculates their normals 3d coat should also calculate the normals, otherwise the normal map will not match to the normals. I tried with XNormal and did not get good results also in 3d Coat, unfortunately. I am not sure anyone has tried this and was successfull:D 

With bake -> Import Coarse mesh you should be able to import the cage. But you really do not need one in this simple case. The good thing in 3d Coat is, that you can adjust the cage with the brush strokes. Read the happy normal baking guide for more infos.

 

Btw. did you try to invert the green channel, when importing the normal map? Helps sometimes. The only quality setting I am aware of for the normal map is the normal map resolution. Calculate 8K and scale down the map, this will get you really good quality. There is no antialiasing setting in 3d Coat unfortunately.

Unbenannt.PNG

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Thanks for the reply.

Yep, After some messing around, I decided to use the "Blender" preset, which is also MikkTspace compliant. "Unreal" engine also works. the Blender preset is the closest I can get. "Unity" did not work. I'm assuming its legacy tangent basis since Unity uses MikkTspace only after version 5.3. Same for substance painter.

Here's the model with the Xnormal baked maps. It's close enough.

importXnormal.thumb.png.de215c0cfc312dab4e86cf5fd0ed8cf9.png

The internally baked version is perfect. Whatever it is, I now have the tangent basis somewhat synced up with substance painter and unity.

I still can't find any documentation regarding the importing of an external bake cage. Could you direct me to one please? If there is one major complain I have with 3D coat, it's documentation. Not every function can be searched on google. Like "import coarse mesh".

Thanks again.

BTW, here's the baking cage.

shape_Cage.obj

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There is no importing of a projection cage. Only what is inside the retopo room is used. In the newer versions of 3DC, you can manually paint on the projection cage. This helps to keep the projection cage closer to the high detail mesh. You can paint (move) those areas of the cage that need it by using a brush method. 

The reason for all the options in normal maps is because of all the ways normal maps can be created or used in other programs.  This makes 3DC powerful in that area, though with power come complexity. Importing external normal maps,  might have to flip a channel, hince  the pop up dialog. I tend to use the open gl version of 3DC if I am importing external normal maps that  were made using open gl.  

I've not had any problems with the Unity preset in 3DC in exporting normal maps from 3DC to Unity.  The exporting under the file menu... 

EDIT: I just noticed the coarse mesh under the bake menu but there is no tool tip on it... Funny, since I always use the built in projection cage, just did not notice the coarse mesh. Sometimes Andrew adds stuff and if he did mention it, I did not read. It's function at the moment I do not know, external cage import maybe..

Edited by digman
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Thanks everyone.

Perhaps Andrew could add that feature some day. Many bakers now work with cages to control the bake angle. Something like Marmoset Tool bag 3 would be cool.

The issue with using the brush tool to control the internally generated cage is that I can't move multiple vertices together. This is needed for evenness.

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  • 6 months later...
On 1/5/2018 at 11:25 PM, digman said:

EDIT: I just noticed the coarse mesh under the bake menu but there is no tool tip on it... Funny, since I always use the built in projection cage, just did not notice the coarse mesh. Sometimes Andrew adds stuff and if he did mention it, I did not read. It's function at the moment I do not know, external cage import maybe..

I found some old reference here

Tip:

Bake a mesh into the Paint Room that has the number of polygons specified

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